Aftertreatment of azoic-dyed cellulose derivatives



A'FTER'ITREATMENT or AZOIC-DYED I 'cnLLULosn DERIVATIVES nail L Youse, Portfluron, linen, and Donald E, Marnon, Glen Rock, N: J., assignors to General Aniline & e 'Corporation, New York, N. Y., acorporatlon of Delaware v v p N Drawi g. Application Apr-i130, 1952,

1 Serial No. 285,314

[2 Claims. (Cl. 8- 48) i This invention relates to improvements in the dyeing of materials 'containing an organic derivative of'cellulose with azo dyes" whereby improved colorations of. good fastness are obtained without objectionably tendering the 'dyedmaterials; and more particularly, it'relates to a tleatment of azo dyed cellulose acetate textile materials of off-shade color and poor lightfastness by subje'cting these materials to a treatment at a temperature inthe'range of 120 to 190- F. for a time in'the range '0)? 3 to30 minutes with an aqueous solution containing about 0.5 to 10% of a polar organic swellingagent for the cellulose derivative, usinglO to'40 parts by weight of the solution per part of the textile material,

and selecting the temperature, time, concentration and amount of solution used so ask) develop the true color or the dye as com ared to the color obtained' therewith on cotton, and simultaneouslydmprove its lightfastness.

male phenol; the provision of such a process wherein "the swelling agent is ethylene; glycol monobutyl etheipthe provision of such a process wherein" the" welling agent is furfural; the rovisiono such a roeess wherein .the

swelling agent is pyridine; thef. provision of uehaproeess wherein thelswellifi'g-agent'is epielilorohydrin; and

other objects which will be' 'apparent' as details or erii bodiments of the inv ntion are set some hereinafter.-

- murder to fa ilitate a clearnnde'istamiing of th in= vention, the following presented specific embodiments are described in detail: l

For one part by weight or cellulose acetate fabric the following baths are prepar d: 20 parts water U v 3% guanidine carbonate (on-the weight of the fabric) 3% sodium naphthalene-sulfonata then thereto add:

3% r 2,3-hydroxy-naplithoiic acid amide previously "brought inte'solutienniaboutlo a sodium hydroxide V methanol) h h Then a dispersion of 6% of; 4-benzoylamino 2,5 diethoxy laniline' in water-is prepared-(using molecular proportions of the 'amine and waterland addedto the above-bath, which is then'heated to-120 F.

.Thecellulose acetate fabric is then introduced into this. bath and treated'thercin 'for45' minutes at 160' F., after which it iswashed with cold water. Then the fabric is treated with: 1

. 2%- sodium nitrite {was weighwi the fabric)" in 10% The azo dyes are particularly desirable for dyeing cellulose acetate and the like'textile materials'inasrnuch. as they provide desirable bright colors which are im- 'pervious to s c-called gas-fading, However, the colors obtained ther'eon'by the usual ingrain dyeing methods ,are of off-shade color as compared to the colors obthey have verypoor lightfastness.

Attempts have been made heretofore to provide azo dyed cellulose acetate materials by treating the dyed material with a very high'concentration of a swelling agent for the cellulose acetate or by treatment at a very high temperature, such as 100 C. It has been found that such treatments are reflected in a very objectionable tendering of the textile material.

It has been found in accordance with the invention tained with the same dyes on cotton; and in manycases that the above discussed drawbacks may be overcome and azo dyed materials containing an organic derivative of cellulose may be provided having true color and good fastness properties without objectionably tendering the materials.

The objects achieved in accordance with the invention include the provision of a process of treating azo dyed materials containing an organic derivative of cellulose and having anofi-shade color and poor lightfastness by subjecting these materials to a treatment at a temperature in the range of 120 to 190 F, fora time in the range of 3 to 30 minutes with an aqueous solution containing about 0.5 to 10% of a polar organic swelling agent for the cellulose derivative, using 10 to '40 parts by weight of the aqueous solution per part of the dyed material, and selecting the time, temperature, concentration and amount of solution so as to develop the true color of the dye and improve its lightfastness without objectionably creasing the material; the provision of such a process applied to textile material containing cellulose acetate; the provision of such a process wherein the swelling agent is a mixture of about 3 to 7% by weight of phthalic anhydride in a water-sob of 56% aqueous'acidic acid I I .for 30 minutes at 75 Rand theno lm'nutes at 160 Followingsthis it is-fivashedandrthen dried. The dyed cloth-was of an undesirable'violet off-shade color,- and its lightfastness-Jontexposure to light .(ina Fade-Ometer) 'wasorlly li) ho'ui's. i A I 'milarlyt dyedcellulose acetate fabric was subjected to atreatmentat180Fi for 7 minutes in the following bath (per part by weightgof the dyed fabric): 20 part-s distilled 'water .25 parrot a; 5.5% mixnire'of'phthalie anhydride in "phenol V 1 0.1 part of polyoxyethylated nonyl phenol containing.

about 8 oxyethyl groups;

and washed and dried.

The resulting material was of a desirable true blue color (compared with the color obtained with this dye on cotton), and it showed a lightfastness of 40 hours in the above-described test. A very desirable feature of the blue dyed material is its imperviousness to fad- 7 ing in the presence of acidic gases, inasmuch as this is a well-known disadvantage of many of the commercial dyestuffs for cellulose acetate.

The desirable blue colored fabric obtained by this process has substantially the same strength properties as the undyed fabric. This is noteworthy when one considers that subjecting the off-colored cloth to a treatment at the boil can give the desired blue shade, but

this treatment results in a very objectionable creasing of the textile fibers. Theinclusion of phthalic anhydride with the phenol avoids the objectionabletendering of the fibers which is known to occur when phenol alone is used, especially at higher concentrations.

Comparable results to the foregoing are achieved using various modifications, such as the following: Other azo dyes which present a similar problem when ingrain dyed as described hereinabove are those prepared from 4- benzoylamino-2,5-dimethoxy-aniline, 2-chlor-4-benzoylamino-S-methoxy-anilirie, 6-benzoylamino-4-methoxy-3- shade; and the dyes which give a brown true color initially have a reddish oibshade. The inventionis applicable to materials containing an organi'c'derivative of cellulose 'such as cellulose acetate, formate, propionate, butyrate,

when used under the above conditions. Instead of phenol in the above-described mixed swelling agent, other wateror mixed acetate propionate or mixed acetate butyrate,

methyl ethyl or benzyl cellulose, and the like. The material may be in the form of films, fibers, yarns, fabrics or filaments. In the case of textile materials, the material may be made entirely of'the cellulose derivative or it may be a mixed material which also contains cotton, natural silk, viscose rayon, or Wool.

The temperature and other conditions for treating the dyed material should be such as to achieve the desired color improvement eifect and at the same time avoid objectionable creasing of the material being treated. A desirable temperature range'is' 120 to 190 F., preferably '140 to 180 F. The treatment time may be in the range of 3 to minutes. The aqueous solution should contain from about 0.5 to 10% by weight of a polar organic swelling agent for the organic derivatives of cellulose, based on the weight of the latter; and the bath should contain an amount in the range of 10 to parts by weight of the aqueous solution per part of-the dyed material. With the higher concentrations and relatively larger amounts of the solution, the color improvement effect may be obtained at lower temperature or treatment time. With the lower concentrations and pro- 1 portions of the solutionused the higher treating temperatures or longer treating times within the above ranges may be required to achieve the desired color improvement. .In any combination within the above ranges, the treating conditionsshould not be sufiiciently strenuous to objectionably crease the cellulose derivative material.

Although the eflect achieved with the above-mentioned -IHiXtUIe of phthalic anhydride with phenolis regarded as particularly unique, desirable results'rnay be obtained with many other chemically inert swelling agents for the cellulose derivative; and for cellulose acetate fabrics, such swelling agents as ethylene glycol monobutyl ether, furfural, pyridine and epichlorohydrin give desirable results soluble phenolic materials may be used, such a cresol, xylenol and the like. Other equivalent surface-active agents may be substituted for-the polyoxyethylated nonyl phenol used in the above-described bath, such as are conventionally used in dyeing treatments.

In view of theyforegoing disclosures, variations and modifications of the invention will be apparent to one skilled "in the art, and his intended to include within the invention all such variations and modifications except as do not come within the scope of the appended claims.

We claim: I

1. In the process of ingrain dyeing of textile materials containing an organic den'vative of cellulose Withan azo dye whereby an off-shade color'is obtained, compared to the true color obtained with said dye on cotton, the improvement which comprises subjecting the thus dyed material to a treatment at a temperature in the range of to 190 F. for a time in the range of 3 to 30 minutes with an aqueous solution containingabout 0.5 to 10% of a polar organic swelling agent for the cellulose derivative 'said organic swelling agent comprising a mixture of about 3 to 7 per cent by weight of phthalic anhydride in phenol, using 10 to 40 parts by weight of the aqueous solution per part of the dyed material, the temperature, time, concentration and amount of solution being selected so as to develop the true color of the dye and improve its light-fastness without objectionably tendering the textile material.

' 2. The process of claim 1 operated at about F. for 7 minutes using-about 20 parts of an aqueous solution containing about 0.5% of polyoxyethylated nonyl phenol containing about ,8 oxyethyl groups and 1.14% of phthalic anhydride in phenol per part of cellulose acetate fabric dyed with diazotized 4-benzoylamino-2,S- .diethoxy aniline coupled with the anilide of- 2,3-hydroxynaphthoic acid.. v

Knoevena gel 11111 14, 1910 2,048,786 Ellis July 28, 1936 2,643,175 Salvin June 23, 1953 OTHER REFERENCES British Rayon and Silk Journal for October 1950, page 48. I 

1. IN THE PROCESS OF INGRAIN DYEING OF TEXTILE MATERIALS CONTAINING AN ORGANIC DERIVATIVE OF CELLULOSE WITH AN AZO DYE WHEREBY AN OFF-SHADE COLOR IS OBTAINED, COMPARED TO THE TRUE COLOR OBTAINED WITH SAID DYE ON COTTON, THE IMPROVEMENT WHICH COMPRISES SUBJECTING THE THUS DYED MATERIAL TO A TREATMENT AT A TEMPERATURE IN THE RANGE OF 120* TO 190* F. FOR A TIME IN THE RANGE OF 3 TO 30 MINUTES WITH AN AQUEOUS SOLUTION CONTAINING ABOUT 0.5 TO 10% OF A POLAR ORGANIC SWELLING AGENT FOR THE CELLULOSE DERIVATIVE SAID ORGANIC SWELLING AGENT COMPRISING A MIXTURE OF ABOUT 3 TO 7 PER CENT BY WEIGHT OF PHTHALIC ANHYDRIDE IN PHENOL, USING 10 TO 40 PARTS BY WEIGHT OF THE AQUEOUS SOLUTION PER PART OF THE DYED MATERIAL, THE TEMPERATURE, TIME, CONCENTRATION AND AMOUNT OF SOLUTION BEING SELECTED SO AS TO DEVELOP THE TRUE COLOR OF THE DYE AND IMPROVE ITS LIGHT-FASTNESS WITHOUT OBJECTIONABLY TENDERING THE TEXTILE MATERIAL. 